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Home / Shop All Teen / Teen Period Swim Square Neck One-Piece
KnixTeen

Teen Period Swim Square Neck One-Piece

$88.00 USD

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Absorbs about 3 regular tampons

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Full coverage style

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Flattering square neckline

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Premium UPF 50+ fabric

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Machine washable

| Black
| Black
| Black
| Black
| Black
| General

Absorbency: Moderate
Drop
Drop
Drop
Drop
Drop

Color: Black

Size:

True to Size

•

Size:

Size and Fit Guide

Free Shipping on orders $100+

Shipping

HOLIDAY SHIPPING

Give the gift of Knix! To receive your order by Dec 24th, please order by the following dates.

All States - Urban Centers (except Hawaii, Alaska)
Standard: Sunday, December 14
Express: Tuesday, December 17

Alaska, Hawaii & Rural
Standard: Wednesday, December 10
Express: Wednesday, December 10
Express shipping is unavailable for international orders:

Africa, Central/South America, and Caribbean
Standard: Wednesday, December 10

Asia, Australia, and New Zealand 
Standard: Thursday, December 11

Europe and the Middle East 
Standard: Thursday, December 11

United Kingdom, France, Germany, Netherlands, Switzerland, and Japan 
Standard: Monday, December 15

Please note: Weather conditions and carrier issues may cause delays. Delivery dates are not guaranteed.

Processing Time
Please allow 1-2 business days for our warehouse team to pack and ship your order. During peak periods such as sales, holidays and product launches, please allow up to 4 business days for us to process your order.

Delivery Time
For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines vary depending on location and do not include processing times.

Shipping Charges
Orders over $100* USD = Free standard Shipping (4-8 business days)**
Expedited = $4.99 USD (3-6 business days)**

Orders under $100* USD = $7.99 USD Standard Shipping (4-8 days)**
Expedited = $9.99 USD (3-6 business days)**

*After discounts, before shipping and taxes. Processing times not included in estimates.
**Military Addresses Excluded. Standard Military Address Shipping = $10.00 USD (est. varies per location)
Easy Returns within 30 Days

Returns

Returns

Sale & Last Call

Items discounted 30% and below are eligible for size exchange or store credit. Items discounted above 30% and above are final sale – no refunds, store credits, or exchanges can be accommodated.

Free Returns

Knix covers the return shipping fees for exchanges and refunds initiated through our Return & Exchange Portal. Exchange orders initiated through our Return & Exchange portal are also eligible for free shipping within the USA and Canada. Please note, the shipping fees on your original order are non-refundable.

Return Policy

Return policy varies by product, please check if your item is refund or exchange eligible by viewing our full policy here.
Rewards Members Earn 88 Points

Swim in Style

A sporty style with a square neckline, built-in shelf bra and removable cups.

Worry-Free Protection

Discreet, built-in protection that absorbs about 3 regular tampons worth.

Stay Sun-Safe

Premium UPF 50+ fabric shields you from UV rays while you relax, swim, and play.

Zoom

| Black
| Black
| Black
| Black
| Black
| General

How to Choose?

Essential

Drop
Drop
Drop
Drop
Drop
  • • Everyday Wear
  • • No leakproof protection
  • tsp
    0 tsp

Heavy

Drop
Drop
Drop
Drop
Drop
  • • heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    about 8-14 tsp
  • pad
    about 1.5-3 regular pads
  • tampon
    about 4-7 super tampons
  • cup
    about 1.5-3 menstrual cups

Light

Drop
Drop
Drop
Drop
Drop
  • • light period days
  • • sweat
  • • discharge
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

Drop
Drop
Drop
Drop
Drop
  • • moderate period days
  • • light bladder leaks
  • • sweat
  • tsp
    about 4-8 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-4 super tampons
  • cup
    about 0.5-3 menstrual cups

Ultra

Drop
Drop
Drop
Drop
Drop
  • • extra heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    about 15-20 tsp
  • pad
    about 1.5-2.5 super pads
  • tampon
    about 7-11 super tampons
  • cup
    about 2-3 menstrual cups
LEAKPROOF SWIM WORKS IN LAYERS

Built-in protection that feels like nothing at all.

Looks just like regular swimwear. Non-swelling liner and patented no-show design.

Soft Top Layer

Top Layer

Smooth and comfortable liner in swimsuit fabric.

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4.6
Rated 4.6 out of 5 stars
Based on 38 reviews
Total 5 star reviews: 33 Total 4 star reviews: 1 Total 3 star reviews: 1 Total 2 star reviews: 1 Total 1 star reviews: 2
89%would recommend this product
ComfortRated 4.7 on a scale of 1 to 5
FitRated -0.3 on a scale of minus 2 to 2
EffectivenessRated 4.7 on a scale of 1 to 5
Ease of UseRated 4.0 on a scale of 1 to 5
Write a Review (Opens in a new window)
38 reviews
  • Rated 5 out of 5 stars
    13 hours ago
    Good fit!

    This is a good fit. The cut offers great coverage. Washes well.

    Chir C.
    Verified Buyer
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  • Rated 5 out of 5 stars
    2 weeks ago
    Lovely fit and comfortable

    Functions as described and has a flattering and comfortable fit.

    Chanta B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    Perfect fit!

    The suit fits true to size and you would never know it is reinforced. It’s quite modest as well. The adjustable straps are a great option.

    Heather G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    Period Swim Square Neck One-Piece

    This is great for my 11-year old for swimming!

    Christina P.
    Verified Buyer
    Was this helpful?
  • Rated 1 out of 5 stars
    3 months ago
    TERRIBLE

    PLEASE DONT BUY THIS PERIOD SWIM. IT WILL NOT PROTECT YOUR DAUGHTER FROM A HUGE LEAK. I WISH I NEVER BOUGTH THIS FOR MY DAUTHER.

    Paola R.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Daughter Approved!!

    Great fit, fun and sporty!! My daughter is begging for more!!

    JEANANNE D.
    Verified Buyer
    Was this helpful?
  • Rated 1 out of 5 stars
    3 months ago
    Beware of using the coupon if you need to return!

    Just a warning for those that use the “welcome” 20 % off coupon. If you use the coupon your items are considered “sale” items and you cannot get your money back if you return the item, you only get store credit. I ordered two different sizes of swimsuits because I wasn’t sure which one would fit my daughter better. Now I can’t get my money back on the one that doesn’t fit just a $70+ credit that I don’t want or need! I read over the return policy before I even bought the stuff to make sure I could return it. It wasn’t on sale so I thought I could get my money back not realizing that after I entered a coupon code at checkout that it made it become a sale item. Just kinda sneaky to me! Not a company I want to do further business with.

    Nita
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Great teen swimsuit

    Fits as described

    Heather G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Great suit for a self conscious tween!

    The adjustable straps are great for a rapidly growing kid

    megan W.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    Loved this!

    My tween loved this! Took the fear away of going into the water and let her just be a normal kid hanging out with friends and family at the pool and the lake!

    Farrah E.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    A hit!

    My discerning 11-year-old granddaughter loves this suit.

    Elaine C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 year ago
    She loves it!

    My daughter loves this swimsuit!

    Stephanie L.
    Verified Buyer
    Was this helpful?